It’s more a consequence of place and purpose. If you’re in a place and don’t use it for the usual purpose, then your motives will be questioned. A store is place to get items. Even if there was no exchange of money, but you went into the store and walked out without anything, it would appear odd.
Go brush your teeth at a library, stand on a sidewalk for a long period of time, ride a bike through a mall. All these things don’t cost money but they are still weird.